Technical Field
[0001] The present invention relates to a rubber member, an adhesive connecting member,
and an optical connection structure.
Background Art
[0002] Optically transmission efficiency of an optical transmission path using optical fibers
is greatly influenced by optically connecting loss at an optical connection part between
the optical fibers or the optical fiber and an optical component such as an optical
semiconductor, etc., in the optical transmission path. As causes of optically connecting
loss in this connection part, imperfect alignment of the optical fibers, inclination
of axes of the optical fibers, clearance between end surfaces of the optical fibers,
etc., can be mentioned, and moreover, inclination, roughness, and swelling of the
end surface of the optical fiber can be also mentioned as causes of optically connecting
loss.
[0003] In order to effectively overcome these causes, a method using a high-precision connecting
apparatus, a method in which high grade polishing processing is carried out on an
end surface of an optical fiber, etc., can be mentioned. However, in the above methods,
there is a problem in that the connection of the optical fibers requires a great deal
of time and effort, and connection cost is increased.
[0004] In addition, as another method, an optical connection structure using an adhesive
connecting member in which optically connecting loss as a problem in optical communication
can be reduced by adhering to a top of an optical fiber, has been proposed (for example,
see Patent Publication 1).
[0005] The optical connection structure will be explained with reference to Fig. 5.
[0006] Fig. 5 is a side view showing an optical connection structure using a conventional
adhesive connecting member.
[0007] Reference numerals 10a and 10b indicate an optical fiber, and reference numeral 21
indicates a conventional adhesive connecting material.
[0008] In Fig. 5, the adhesive connecting member 21 is intervened in an adhered condition
between connecting surfaces of the optical fiber 10a and the optical fiber 10b. The
two optical fibers 10a and 10b are contacted by way of the adhesive connecting member
21, and thereby the optical fibers are optically connected.
[0009] However, the conventional adhesive connecting member cannot be easily retried if
it fails to adhere at a suitable position. In addition, in the case in which the conventional
adhesive connecting member is used for a connector that was strongly contacted, such
as an SC connector, an LC connector, etc., is often broken.
[0010] Patent Publication 1 is Japanese Unexamined Patent Application Publication No.
2006-221031.
DISCLOSURE OF THE INVENTION
PROBLEMS SOLVED BY THE INVENTION
[0012] The present invention was completed in view of the above-described circumstances,
and an object of the present invention is to provide a rubber member, an adhesive
connecting member and an optical connection structure, in which the optically connecting
loss can be decreased and the positioning can be retried without breaking.
MEANS FOR SOLVING THE PROBLEMS
[0013] According to the present invention, the above problem can be solved by the following
technical composition.
- (1) A rubber member optically connecting (a) an optical transmission medium or an
optical component and (b) another optical transmission medium or another optical component
by intervening between the (a) and the (b).
- (2) An adhesive connecting member comprising a rubber member having a refractive index
of 1.35 to 1.55 and an adhesive having a refractive index of 1.35 to 1.55.
- (3) The adhesive connecting member according to (2), wherein the rubber member and
the adhesive are laminated.
- (4) The adhesive connecting member according to (2), wherein the rubber member is
styrenic rubber.
- (5) The adhesive connecting member according to (2), wherein the rubber member is
a copolymer having a polystyrene-poly(ethylene/propylene)block - polystyrene structure
or a copolymer having a polystyrene-poly(ethylene/butylene)block-polystyrene structure.
- (6) The adhesive connecting member according to (2), wherein the rubber member has
a styrene content of 1 to 50 weight %.
- (7) The adhesive connecting member according to (2), wherein the rubber member has
type A durometer hardness by Japan Industrial Standard (hereinafter referred to as
JIS) of 50 to 100.
- (8) The adhesive connecting member according to (2), wherein the rubber member has
a thickness of 1 to 30 µm.
- (9) The adhesive connecting member according to (2), wherein the ratio of thickness
of the rubber member and the adhesive is 1:1 to 1:3.
- (10) The adhesive connecting member according to (2), wherein the rubber member is
an acrylic rubber.
- (11) The adhesive connecting member according to (10), wherein the acrylic rubber
has a glass transition temperature (Tg) of -30 °C.
- (12) The adhesive connecting member according to (10), wherein the acrylic rubber
has a Mooney viscosity ML1+4(100 °C) of 40 or more.
- (13) The adhesive connecting member according to (10), wherein the acrylic rubber
has a transmittance at a wavelength of 850 to 1700 nm of 85% or more.
- (14) The adhesive connecting member according to (2), wherein the adhesive comprises
acrylic adhesive and hardener, and the hardener is epoxy hardener or isocyanate hardener.
- (15) An optical connection structure in which (a) an optical transmission medium or
an optical component and (b) another optical transmission medium or another optical
component are connected by way of an adhesive connecting member, wherein the adhesive
connecting member comprises a rubber member and an adhesive.
- (16) The optical connection structure according to (15), wherein the rubber member
and the adhesive are laminated.
[0014] The present invention can provide a rubber member, an adhesive connecting member
and an optical connection structure, in which the optically connecting loss can be
decreased and the positioning can retried without breaking.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015]
Fig. 1 is a side view showing Embodiment 1 of an optical connection structure using
an adhesive connecting member of the present invention.
Fig. 2 is a perspective view showing Embodiment 2 of an optical connection structure
using an adhesive connecting member of the present invention.
Fig. 3 is a plane view showing Embodiment 2 of an optical connection structure using
an adhesive connecting member of the present invention.
Fig. 4 is a plane view showing Embodiment 3 of an optical connection structure using
an adhesive connecting member of the present invention.
Fig. 5 is a side view showing an optical connection structure using a conventional
adhesive connecting member.
EXPLANATION OF REFERENCE SYMBOLS
[0016]
10a, 10b... optical fiber,
11a-14a, 11b-14b... optical fiber,
15a, 15b... optical fiber tape core,
21... conventional adhesive connecting member,
22... adhesive connecting member of the present invention,
22a... adhesive,
22b... rubber member,
30... optical component,
47a, 47b... guide pin,
75a, 75b... MT connector,
80... SC connector,
90... adopter for SC connector,
H... guide pin insertion hole
BEST MODE FOR CARRYING OUT THE INVENTION
[0017] Embodiment 1 will be explained with reference to Fig. 1.
[0018] Fig. 1 is a side view showing Embodiment 1 of an optical connection structure using
an adhesive connecting member of the present invention.
[0019] Reference numeral 10a indicates an optical fiber, which is an optical transmission
medium, reference numeral 10b indicates an optical fiber, which is another optical
transmission medium, reference numeral 22 indicates an adhesive connecting member,
reference numeral 22a indicates an adhesive, and reference numeral 22b indicates a
rubber member.
[0020] The optical connection structure according to Embodiment 1 of the present invention
is formed by connecting the optical fiber 10a and the optical fiber 10b by way of
the adhesive connecting member 22, and the adhesive connecting member 22 consists
of the rubber member 22b and the adhesive 22a.
[0021] It is preferable that the rubber member 22b and the adhesive 22a be laminated. Here,
the adhesive 22a and the rubber member 22b may be arranged so as to contact therewith,
and another refractive index matching agent may be sandwiched between the adhesive
22a and the rubber member 22b.
[0022] The optical connection structure of Embodiment 1 has a structure in which two optical
fibers 10a and 10b are optically connected by contacting therewith by way of the adhesive
connecting member 22, as shown in Fig. 1.
[0023] Here, the optical fiber 10a and the adhesive connecting member 22 are firmly adhered.
[0024] The adhesive connecting member 22 and the optical fiber 10b are not adhered.
[0025] Therefore, the adhesive connecting member 22 and the optical fiber 10b are separated
by detaching the optical fiber 10a and the adhesive connecting member 22, and thereby,
the optical fiber 10b can be easily retried.
[0026] Here, although the adhesive connecting member 22 is contacted with the optical fiber
10b, each time the positioning is retried, it is not broken since the rubber member
22b having remarkably higher strength than that of the adhesive is contacted.
[0027] It is preferable that the refractive index of the rubber member 22b in the present
invention be 1.35 to 1.55, and it is more preferable that it be 1.40 to 1.50.
[0028] According to the rubber member 22b in the present invention, the optical fiber 10a
and the optical fiber 10b can be optically connected by intervening between the optical
fiber 10a and the optical fiber 10b.
[0029] It is preferable that the rubber member 22b be styrenic rubber or acrylic rubber.
It is preferable that the styrenic rubber be any one of styrene ethylene rubber, styrene
propylene rubber, and styrene butadiene rubber, and more preferable that it be a copolymer
having a polystyrene-poly(ethylene/propylene)block-polystyrene structure or copolymer
having a polystyrene-poly(ethylene/butylene)block-polystyrene structure.
[0030] In addition, it is preferable that the styrene content of the rubber member 22b be
1 to 50 weight %, and it is more preferable that it be 10 to 30 weight %.
[0031] Furthermore, it is preferable that the primary component of the acrylic rubber be
an alkyl acrylate such as ethyl acrylate, butyl acrylate, etc.
[0032] Additionally, it is preferable that the glass transition temperature (Tg) of the
acrylic rubber -30 °C or more, and it is more preferable that it be -20 °C or more.
When the glass transition temperature (Tg) is below -30 °C, the acrylic rubber is
easily broken by increasing tackiness at the surface thereof.
[0033] In addition, it is preferable that the Mooney viscosity ML
1+4(100 °C) of the acrylic rubber be 40 or more, and it is more preferable that it be
50 or more.
[0034] It is preferable that the acrylic rubber be superior in transparency, and it is preferable
that light transmittance at a wavelength to be used, that is, a wavelength of 850
to 1700 nm, be 85% or more. It is relatively easy for the transparency of the acrylic
rubber to be increased by adjusting a cross-linking agent and hardener. It is more
preferable that the light transmittance at a wavelength to be used be 90% or more.
[0035] Furthermore, the rubber material 22b preferably has type A durometer hardness by
JIS of 10 to 100, and more preferable has of 50 to 100.
[0036] Here, the above hardness is a value measured according to JIS K-6253.
[0037] It is preferable that thickness of the rubber member 22b be 1 to 30 µm, and it is
more preferable that it be 3 to 20 µm.
[0038] When the thickness is under 1 µm, the rubber member 22b is easily broken, and when
it is greater than 30 µm, the optically connecting loss is increased. Here, it is
most preferable that the hardness be 50 or more and the thickness be 3 to 20 µm, since
it is difficult to break, and the optically connecting loss is also small.
[0039] As a rubber member in the present invention, commercially available types of rubber
may be used.
[0040] Next, it is preferable that the refractive index of the adhesive 22a be 1.35 to 1.55,
and it is more preferable that it be 1.40 to 1.50.
[0041] As the adhesive 22a, various polymer adhesives such as acrylic adhesive, epoxy adhesive,
vinyl adhesive, silicone adhesive, rubber adhesive, urethane adhesive, methacrylic
adhesive, nylon adhesive, bisphenol adhesive, diol adhesive, polyimide adhesive, fluoridated
epoxy adhesive, fluoridated acrylic adhesive, etc., can be used. Additionally, these
adhesives may be used in combination or by adding hardener or fluorocarbon resin,
as necessary.
[0042] Of these, the acrylic adhesive and the silicone adhesive are preferably used, because
of adhesiveness and other characteristics.
[0043] The acrylic adhesive used in the present invention means polymers constructed of
alkyl ester in which a basic structure is acrylic acid and carbon number is 2 to 12,
or alkyl ester in which a basic structure is methacrylic acid and a carbon number
of 4 to 12, as a primary monomer. Specifically, an alkyl ester of an acrylic acid
such as ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate,
lauryl acrylate, benzyl acrylate, etc., and an alkyl ester of methacrylic acid such
as n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, lauryl
methacrylate, benzil methacrylate, etc., can be mentioned. In addition, as a monomer
for copolymerizing these primary monomers, methyl acrylate, methyl methacrylate, ethyl
methacrylate, propyl methacrylate, vinyl acetate, acrylonitrile, methacrylonitrile,
acrylamide, styrene, etc., can be used.
[0044] It is preferable that the acrylic adhesive be a material that is superior in transparency,
and it is preferable that the light transmittance at a wavelength to be used, that
is, at a wavelength of 850 to 1700 nm, be 85% or more. The acrylic adhesive is material
in which the transparency can be relatively easily increased by adjusting a cross-linking
agent and a hardener. It is more preferable that the light transmittance at a wavelength
to be used be 90% or more.
[0045] The silicone adhesive used in the present invention means an adhesive in which a
frame of a main chain includes an Si-O-Si bonding (siloxane bonding), and it is constructed
of silicone rubber or silicone resin.
[0046] These are solidified and filmed by applying in a condition dissolved by organic solvent.
[0047] A primary polymer of the silicone rubber is straight-chained polydimethylsiloxane,
and it also includes polymers in which some of the methyl groups are substituted with
phenyl groups or vinyl groups.
[0048] In addition, as a silicone resin, resins having a complicated three-dimensional structure
and having a molecular weight of about 3,000 to 10,000, can be used, in order to function
as an adhesion imparting resin.
[0049] Here, a cross-linking agent, softener, adhesion modifier, and other additives may
be added to the silicone adhesive, in order to adjust adhesive power or wettability
and impart water resistance or heat resistance.
[0050] The silicone adhesive is characterized in that adhesive heat resistance is superior
and adhesive power is superior under high temperatures or in a low temperature environment.
[0051] Therefore, according to the optical connection structure in which the silicone adhesive
is intervened between an optical transmission medium and another optical transmission
medium or an optical component, adhesion of the connection can be maintained and a
connection condition which is always stabilized can be maintained, even under a high
temperature environment (to 250 °C) or under a low temperature environment (to -50
°C).
[0052] In addition, the silicone adhesive can be preferably separated from an adhered structure
without curing or yellowing, even if it is heated to a high temperature.
[0053] Furthermore, the silicone adhesive is superior in electrical insulation, chemical
resistance, weather resistance, and water resistance, and it can be adhered to various
materials, for example, an optical fiber in which a cladding layer is coated with
a fluorocarbon resin, etc.
[0054] Additionally, it can also be effectively used in an optical waveguide or an optical
component, since the adhesion is exhibited to a member made of a fluorocarbon resin
such as fluorine polyimide, etc.
[0055] As a hardener, various epoxy hardeners and various isocyanate hardeners, etc., can
be used. In addition, the adhesive may be cured by using a catalyst.
[0056] The adhesive power can be adjusted by combination of the adhesive and the hardener,
a mixing amount thereof, etc.
[0057] It is necessary that the adhesive 22a have strong adhesive power so that the adhesive
connecting member 22 does not separate from the optical fiber 10a, and it is preferable
that the adhesive power be 20 to 2500 gf/25 mm, and it is more preferable that it
be 100 to 2500 gf/25 mm.
[0058] Here, the adhesive power is a value measured according to JIS Z0237 180-degree peeling-off
adhesive power.
[0059] It is preferable that a thickness of the adhesive 22a be 5 to 30 µm, and it is more
preferable that it be 5 to 20 µm.
[0060] When the thickness is under 5 µm, the optical transmission medium and the optical
component are not reliably connected in the case in which the surface of the optical
transmission medium or the optical component is uneven, and in contrast, when it exceeds
30 µm, the optically connecting loss is increased.
[0061] It is preferable that the thickness ratio of the rubber member 22b and the adhesive
22a be from 1:1 to 1:3 from a viewpoint of handling.
[0062] In the present invention, the adhesive connecting member 22 comprises the rubber
member 22b having a refractive index of 1.35 to 1.55 and the adhesive 22a having a
refractive index of 1.35 to 1.55.
[0063] It is preferable that a difference of the rubber member 22b and the adhesive connecting
member 22 be 0.03 or less.
[0064] The refractive index of the adhesive connecting member in the present invention may
be any of approximate refractive indexes to (a) an optical transmission medium or
an optical component and (b) another optical transmission medium or another optical
component and is not limited to a specific range; however, it is preferable that the
difference of an average value of the refractive indexes (a) and (b) and the refractive
index of the adhesive connecting member 22 be 0.1 or less, and it is more preferable
that it be 0.05 or less, from a viewpoint of the optically connecting loss due to
avoidance of Fresnel reflection.
[0065] The adhesive connecting member 22 may be a sheet-like adhesive connecting member
in a film shape, and it may be transformed by having elasticity.
[0066] As an optical transmission medium used in the present invention, optical waveguides,
etc., can be mentioned in addition to the above optical fibers; however, they are
not limited to specific types, and they may be any in which light is transmitted therein.
In addition, the optical fiber is not specifically limited in any particular way,
and it may be suitably selected depending on application thereof. For example, an
optical fiber consisting of material such as quartz, plastic, etc., can be used. In
addition, as an optical waveguide, a quartz optical waveguide, a polyimide optical
waveguide, a PMMA optical waveguide, an epoxy optical waveguide, etc., can be utilized.
[0067] Furthermore, two optical transmission media to be used can be connected, even if
the types thereof are different. In addition, in the case in which the optical transmission
media in which core diameters and mode field diameters are the same, they can be applied
to the present invention, even if the outer diameters are different. Here, the number
of the optical fibers and the number of the optical waveguides are not limited to
a specific range, and an optical fiber tape core comprising plural optical fibers
can be used.
[0068] As an optical component used in the present invention, an optical lens, a filter,
a measuring apparatus, a laser diode, a photodiodes, etc., can be mentioned, and they
are not limited to specific types. As an optical lens, for example, lenses having
various shapes such as a convex lens, a concave lens, a convexoconcave lens, a flat-convex
lens, an aspherical lens, and a collimate lens, a rod lens, etc., can be mentioned,
and as a filter, for example, a multilayer filter, a polyimide filter, etc., can be
mentioned in addition to a filter for general optical communication.
[0069] Next, Embodiment 2 will be explained with reference to Fig. 2 and Fig. 3.
[0070] Fig. 2 is a perspective view showing Embodiment 2 of an optical connection structure
of the present invention, and Fig. 3 is a plane view showing Embodiment 2 of an optical
connection structure of the present invention.
[0071] Reference numerals 11a to 14a, and 11b to 14b, indicate optical fibers, reference
numeral 15a indicates an optical fiber tape core consisting of 4 cores which is an
optical transmission medium, reference numeral 15b indicates an optical fiber tape
core consisting of 4 cores, which is the other optical transmission medium, reference
numerals 47a and 47b indicate guide pins, reference numerals 75a and 75b indicate
an MT connector, and reference symbol H indicates a guide pin insertion hole.
[0072] In Fig. 2, an adhesive connecting member 22 is intervened at a connecting surface
between the MT connector 75a and the MT connector 75b.
[0073] As shown in Fig. 2A, two MT connector 75a and MT connector 75b are positioned by
guide pins 47 and are contacted by way of an adhesive connecting member 22, and thereby,
as shown in Fig. 2B, optical fiber tape cores 15a and 15b are optically connected.
[0074] Here, the MT connector 75a and the adhesive connecting member 22 are firmly adhered.
[0075] The adhesive connecting member 22 and the MT connector 75b are not adhered.
[0076] Therefore, the adhesive connecting member 22 and the MT connector 75b are separated
by pulling down the MT connector 75a and the MT connector 75b, and as a result, the
positioning can be easily retried.
[0077] Here, the adhesive connecting member 22 is contacted to the MT connector 75b at every
positioning; however, since it is contacted by the rubber member 22b having a remarkably
higher hardness than that of the adhesive, it is therefore not broken.
[0078] Furthermore, the present invention will be explained with reference to Fig. 3.
[0079] As shown in Fig. 3A, the adhesive connecting member 22 is arranged between the MT
connector 75a and the MT connector 75b.
[0080] Next, as shown in Fig. 3B, the adhesive connecting member 22 is adhered to the MT
connector 75a. In this case, the adhesive 22a is arranged so as to contact with the
MT connector 75a.
[0081] Then, the MT connector 75a and the MT connector 75b are contacted by way of the adhesive
connecting member 22, as shown in Fig. 3C, while the positioning is carried out by
inserting the guide pins 47a and 47b into the guide pin insertion hole H. Thereby,
the rubber member 22b of the adhesive connecting member 22 and the MT connector 75b
are contacted, and as a result, an optical connection structure is produced.
[0082] A slight gap in contact angle is generated even if the guide pins 47a and 47b for
positioning are used, and therefore, according to the present invention, a suitable
connection can be easily carried out by retrying the positioning, and thereby, operations
at a working site can be drastically reduced.
[0083] Next, Embodiment 3 of the present invention will be explained with reference to Fig.
4.
[0084] Fig. 4 is a plane view showing Embodiment 3 of an optical connection structure of
the present invention.
[0085] Reference numeral 30 indicates an optical component, reference numeral 80 indicates
an SC connector, and reference numeral 90 indicates an adapter for an SC connector.
[0086] As shown in Fig. 4, the adhesive connecting member 22 is arranged between the SC
connector 80 and the adapter 90 for an SC connector.
[0087] Then, the adhesive connecting member 22 is adhered to the SC connector 80. In this
case, an adhesive 22a is arranged so as to contact the SC connector 80.
[0088] Next, the SC connector 80 is inserted into the adapter 90 for an SC connector, and
is contacted by way of the adhesive connecting member 22 to an optical component 30.
Thereby, the rubber member 22b of the adhesive connecting member 22 and the optical
component 30 are contacted, and the optical connection structure is produced.
[0089] The adhesive connecting member 22 of the present invention is not broken, even if
it is used for a connector which is strongly contacted, such as an SC connector, an
LC connector, etc., since it is contacted by the rubber member 22b having a remarkably
higher hardness than that of the adhesive.
[0090] Next, a production method for the adhesive connecting member of the present invention
will be explained.
[0091] The rubber member is laminated on one protection film such as a PET film, the adhesive
is applied to the rubber member, and then, another protection film such as a PET film
is laminated on the adhesive, and the adhesive connecting member is thereby produced.
[0092] Here, the protection film is not always used; however, it is preferable that the
adhesive connecting member be produced using the protection film and the protection
film be separated when the adhesive connecting member is used, from a viewpoint of
prevention from staining and easy handling.
[0093] Next, a production method of the optical connection structure of the present invention
will be explained.
[0094] An adhesive connecting member is cut to a desired size, and an adhesive of the adhesive
connecting member is contacted with (a) an optical transmission medium or an optical
component, and then a rubber member of the adhesive connecting member is contacted
with (b) another optical transmission medium or another optical component, and thereby,
the optical connection structure of the present invention is produced. Here, the order
of the contact is not limited to the above.
[0095] Of course, even when the positioning has failed, (a) an optical transmission medium
or an optical component and (b) another optical transmission medium or another optical
component, can be easily reconnected, since the rubber member and (b) the other optical
transmission medium or the other optical component are peeled off by pulling back
(a) an optical transmission medium or an optical component.
EXAMPLES
[0096] In the following, the present invention will be explained by using Examples.
Example 1
[0097] First, an adhesive connecting member was produced as follows.
[0098] As a material of the adhesive, a material A was prepared.
Material A
[0099] 
[0100] Here, the refractive index was measured by using a light source having a wavelength
of 1310 nm (hereinafter the same shall apply).
[0101] As a material of the rubber member, a material X was prepared.
Material X
[0102] Copolymer having a polystyrene-poly(ethylene/propylene)block-polystyrene structure
(styrene content: 18 weight %, type A durometer hardness by JIS: 67, refractive index
at 20 °C: 1.428)
[0103] The material X was applied at a thickness of 5 µm on a PET film having a thickness
of 50 µm.
[0104] Then, the material A was applied at a thickness of 15 µm on the surface of the material
X, and a PET film having a thickness of 50 µm was laminated thereon, and therefore,
an adhesive connecting member of Example 1 was produced.
[0105] Next, an optical connection structure was produced as follows.
[0106] First, the above adhesive connecting member was cut at a predetermined size, and
a connecting surface of an SC connector (produced by Sumitomo Electric Industries
Ltd., trade name: single core optical connector SC) which holds a quartz type single-mode
optical fiber (produced by Sumitomo Electric Industries Ltd., outer diameter: 0.25
mm, refractive index at 20 °C: 1.452) was contacted with and adhered to an adhesive
of the adhesive connecting member. Then, the SC connector was connected with a measuring
apparatus (produced by Advantest Corporation, trade name: OPTICAL MULTI POWER METER
Q8221), which was an optical component, by way of an adapter for an SC connector (produced
by Sumitomo Electric Industries Ltd., trade name: optical adapter SC-SC (plastic)).
Thereby, the rubber member in the adhesive connecting member and the measuring apparatus
were contacted, and the optical connection structure of Example 1 was produced.
Example 2
[0107] An adhesive connecting member and an optical connection structure of Example 2 were
produced in the same manner as that of Example 1, except that a material B was used
as a material of the adhesive instead of the material A.
Material B
[0108] 
Example 3
[0109] An adhesive connecting member and an optical connection structure of Example 3 were
produced in the same manner as that of Example 1, except that a material C was used
as a material of the adhesive instead of the material A.
Material C
[0110] 
Example 4
[0111] An adhesive connecting member and an optical connection structure of Example 4 were
produced in the same manner as that of Example 1, except that a material Y was used
as a rubber member instead of the material X.
Material Y
[0112] Copolymer having a polystyrene-poly(ethylene/butylene)block-polystyrene structure
(styrene content: 30 weight %, type A durometer hardness by JIS: 77, refractive index
at 20 °C: 1.479)
Example 5
[0113] An adhesive connecting member and an optical connection structure of Example 5 were
produced in the same manner as that of Example 1, except that a material V was used
as a rubber member instead of the material X.
Material V
[0114] Acrylic rubber (produced by Unimatec Co., Ltd., trade name: NOXTITE A-5098, refractive
index: 1.48, Tg: -17 °C, Mooney viscosity ML
1+4 (100 °C): 55, transmittance in a thickness of 15 µm at a wavelength of 850 to 1700
nm: 91%, type A durometer hardness by JIS: 65)
[0115] Here, the transmittance was measured by using a spectrophotometer (produced by Shimadzu
Corporation, trade name: UV-PC3100) (hereinafter the same shall apply).
Example 6
[0116] An adhesive connecting member and an optical connection structure of Example 5 were
produced in the same manner as that of Example 1, except that a material W was used
as a rubber member instead of the material V.
Material W
[0117] Acrylic rubber (produced by Zeon Corporation, trade name: Nipol AR-71, refractive
index: 1.46, Tg: -15 °C, Mooney viscosity ML
1+4 (100 °C): 50, transmittance in a thickness of 15 µm at a wavelength of 850 to 1700
nm: 91%, type A durometer hardness by JIS: 71)
Example 7
[0118] An adhesive connecting member and an optical connection structure of Example 7 were
produced in the same manner as that of Example 6, except that a material C was used
as a material of the adhesive instead of the material A.
Material C
[0119] 
Example 8
[0120] An adhesive connecting member and an optical connection structure of Example 8 were
produced in the same manner as that of Example 5, except that a material Z was used
as a rubber member instead of the material V.
Material Z
[0121] Acrylic rubber (produced by Zeon Corporation, trade name: Nipol AR-53L, refractive
index: 1.47, Tg: -32 °C, Mooney viscosity ML
1+4 (100 °C): 34, transmittance in a thickness of 15 µm at a wavelength of 850 to 1700
nm : 93%, type A durometer hardness by JIS: 74)
Example 9
[0122] An adhesive connecting member and an optical connection structure of Example 9 were
produced in the same manner as that of Example 5, except that a rubber member having
a thickness of 15 µm was used.
Example 10
[0123] An adhesive connecting member and an optical connection structure of Example 10 were
produced in the same manner as that of Example 5, except that a rubber member having
a thickness of 35 µm was used.
Example 11
[0124] An adhesive connecting member and an optical connection structure of Example 11 were
produced in the same manner as that of Example 5, except that a rubber member having
a thickness of 2 µm was used.
Example 12
[0125] An adhesive connecting member and an optical connection structure of Example 12 were
produced in the same manner as that of Example 5, except that a rubber member having
a thickness of 0.5 µm was used.
Comparative Example 1
[0126] An adhesive connecting member and an optical connection structure of Comparative
Example 1 were produced by using only the material A.
Comparative Example 2
[0127] An adhesive connecting member and an optical connection structure of Comparative
Example 2 were produced by using only the material B.
Comparative Example 3
[0128] An adhesive connecting member and an optical connection structure of Comparative
Example 3 were produced by using only the material C. With respect to the optical
connection structures of Examples and Comparative Examples, the materials used are
shown in Table 1.
Table 1
|
Adhesive |
Rubber member |
Thickness of rubber member (µm) |
Example 1 |
Material A |
Material X |
5 |
Example 2 |
Material B |
Material X |
5 |
Example 3 |
Material C |
Material X |
5 |
Example 4 |
Material A |
Material Y |
5 |
Example 5 |
Material A |
Material V |
5 |
Example 6 |
Material A |
Material W |
5 |
Example 7 |
Material C |
Material W |
5 |
Example 8 |
Material A |
Material Z |
5 |
Example 9 |
Material A |
Material V |
15 |
Example 10 |
Material A |
Material V |
35 |
Example 11 |
Material A |
Material V |
2 |
Example 12 |
Material A |
Material V |
0.5 |
Comparative Example 1 |
Material A |
- |
Comparative Example 2 |
Material B |
- |
Comparative Example 3 |
Material C |
- |
[0129] The optical connection structures of the Examples and the Comparative Examples were
evaluated by the following methods.
Evaluation Methods
Initial optically connecting loss
[0130] A connecting surface of an SC connector (produced by Sumitomo Electric Industries
Ltd., trade name: single core optical connector SC) which holds a quartz type single-mode
of an optical fiber (produced by Sumitomo Electric Industries Ltd., outer diameter:
0.25 mm, refractive index at 20 °C: 1.452) was polished, and this was then connected
with a measuring apparatus which was an optical component, by way of an adapter for
an SC connector (produced by Sumitomo Electric Industries Ltd., trade name: optical
adapter SC-SC (plastic)). A light from an LED of 1550 nm was emitted from the tip
of the optical fiber, and the power of the light emitted to the measuring apparatus
was measured as a standard value.
[0131] Next, with respect to the optical connection structures of the Examples and the Comparative
Examples, a light from an LED of 1550 nm was emitted from the tip of the optical fiber,
and the power of the light emitted to the measuring apparatus was measured as an initial
value.
[0132] The difference between the standard value and the initial value was calculated, as
an initial optically connecting loss [dB]. Here, when the initial optically connecting
loss was within 0.3 dB, there was no problem in practical use, and it was preferably
within 0.2 dB.
Frequency of success reconnection
[0133] With respect to the optical connection structures of the Examples and the Comparative
Examples, a light from an LED of 1550 nm was emitted from the tip of the optical fiber,
and the power of the light emitted to the measuring apparatus was measured as an initial
value.
[0134] Next, the connection was once released by detaching the SC connector from the adapter
for the SC connector, and then the SC connector was reconnected to the adapter for
the SC connector. Subsequently, the power of the light was measured and difference
[dB] between the measured value and the initial value was recorded.
[0135] When the difference between the measured value and the initial value was within 0.3
dB, it was judged that the reconnection was a success.
[0136] Then, the connection release, the reconnection, and the measurement were repeated,
until the difference between the measured value and the initial value repeatedly exceeds
0.3 dB or frequency of measurement is 100 times, and the frequency of successful reconnections
was examined.
[0137] The above results are shown in Table 2.
Table 2
|
Initial optically connection loss (dB) |
Successful reconnections |
Example 1 |
0.1 |
100 |
Example 2 |
0.2 |
100 |
Example 3 |
0.1 |
100 |
Example 4 |
0.2 |
100 |
Example 5 |
0.2 |
100 |
Example 6 |
0.2 |
100 |
Example 7 |
0.1 |
100 |
Example 8 |
0.2 |
15 |
Example 9 |
0.2 |
100 |
Example 10 |
0.3 |
100 |
Example 11 |
0.05 |
65 |
Example 12 |
0.05 |
12 |
Comparative Example 1 |
0.1 |
0 |
Comparative Example 2 |
0.1 |
0 |
Comparative Example 3 |
0.05 |
2 |
Evaluation results
[0138] In Examples 1 to 12, there was no problem in practical use with respect to both of
the initial optically connecting loss and the frequency of successful reconnections.
In particular, in the Examples 1 to 7 and 9 to 10, the frequency of successful reconnections
was superior.
[0139] In contrast, in the Comparative Examples 1 to 3, there was no problem in practical
use with respect to the initial optically connecting loss; however, there was a problem
in practical use since the frequency of reconnection was 2 times or less.
[0140] In addition, in Comparative Examples 1 to 3, the adhesive connecting member was broken
by releasing the connection, and there was a problem in practical use.